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Testicular and epididymal appendages in the cynomolgus macaque (Macaca fascicularis)

M Zöller1, S Friderichs-Gromoll, J Kaspareit

  • 1Covance Laboratories GmbH, Department of Pathology, Münster, Germany. martina.zoeller@covance.com

Journal of Medical Primatology
|September 8, 2009
PubMed
Abstract

Insights

Rudimentary testicular and epididymal structures, including appendix testis and appendix epididymidis, were identified in cynomolgus macaques. Recognizing these vestigial tissues is crucial for accurate toxicological research and necropsy evaluations in non-human primates.

Area of Science:

  • Veterinary Anatomy
  • Developmental Biology
  • Primate Research

Background:

  • Vestigial remnants of mesonephric and paramesonephric ducts are known human testicular and epididymal abnormalities.
  • These developmental anomalies can impact reproductive system morphology.

Purpose of the Study:

  • To document and characterize vestigial testicular and epididymal structures in cynomolgus macaques.
  • To highlight the importance of identifying these structures in non-human primate research.

Main Methods:

  • Macroscopic and histological examination of cynomolgus macaque reproductive organs.
  • Histological and immunohistochemical analyses of observed appendages.

Main Results:

  • Three forms of testicular and epididymal appendages were observed: appendix testis, appendix epididymidis, and vasa aberrantia.
  • Appendix testis and epididymidis showed fibromuscular cores and pseudostratified columnar epithelium.
  • Vasa aberrantia were duct-like or cystic structures lined with simple cuboidal to columnar epithelium.

Conclusions:

  • Awareness of these rudimental tissues in non-human primates is essential.
  • Accurate identification prevents misdiagnosis during routine necropsy and histological examinations in toxicological studies.
  • This knowledge aids in determining actual incidence rates in non-human primate species used in research.

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